Population Statistics acting manager Deb Potter said the declining divorce numbers were in line with a trend stretching back to 2005.
There were 301 civil unions celebrated in 2011, of which 77 per cent were between same-sex couples.
The first civil unions were celebrated in New Zealand on April 29, 2005.
Since then 2,152 residents have registered a civil union. Up to 31 December 2011, only 83 of the unions had been dissolved.
Key figures for 2011
* 20,231 marriages.
* 14,049 first marriages, 6,182 remarriages.
* 2,200 additional marriages registered to overseas residents.
* 8,551 divorces.
* 301 civil unions.
* 565 couples married on November 11, or 11/11/11, compared to 87 on an average Friday.
- HERALD ONLINE